174 MODERN FOREST ECONOMY. 



fellings should be made to secure in the highest degree 

 what was desired sustained production of wood by the 

 forest, and a maximum of quantity, a maximum of profit, 

 or a maximum of value, in the wood produced. 



These are only adduced as specimens of the kinds of 

 observations which have been made, accumulated, and 

 made use of in determining the most advantageous form 

 exploitation should take, and such observations are being 

 made still. 



In connection with many of the Schools of Forestry on 

 the Continent of Europe there have been established 

 National Experimental Stations at which, as at those con- 

 nected with Schools of Forestry in Austria, attention is 

 given to such matters while at others, other matters 

 bearing upon the advancement of forest science, and of 

 forest economy, or applied forest science, are being 

 attended to, and subjected to experiment. Before the last 

 century had closed endeavours were being made in Ger- 

 many to turn to account discoveries of the kind indicated 

 which had been made ; and early in the present century 

 great and rapid progress in this was made. The result of all 

 this has been such a development of the system of exploi- 

 tation carried on in sections of forest, that the produce of 

 the clearing of one section is supplemented by the produce 

 of thinnings in one or more others, these thinnings being 

 so arranged, in accordance with the knowledge which has 

 been acquired of the physiology of arborescent vegetation 

 under different conditions, as gradually to prepare each 

 section for being cleared, while, meanwhile the vigorous 

 growth of the standing trees in it is promoted by the 

 operation, and the continued growth of these trees is made 

 subservient to the growth of a succeeding crop of trees 

 produced from self-sown seed : all which is so arranged 

 that every operation of the forester within the area of the 

 forest upon which he is engaged shall tend to secure a 

 sustained production of wood, combined with a natural 

 reproduction of the forests, and an improved condition of 



